Specialized farming equipment has been developed to facilitate the cultivating of fields, planting of crops in fields, and harvesting of crops from fields. Root-type crops particularly require specialized handling equipment. Root-type crops include peanuts as well as other crops which grow the harvestable product below ground. Harvesting root-crops requires removing the root crop from the ground, removing dirt from the crop product, and typically drying the crop to facilitate separation of the crop product from the plants during final harvesting.
Peanuts are a particular type of root crop for which specialized harvesting apparatus has been developed. Peanuts are a vine-type root crop. The specialized equipment handles the continuous vines which grow on the ridges of the crop rows in the field. Peanut harvesters are generally referred to as digger/shaker/inverters. The peanut harvesting apparatus has a digging assembly from which a pair of angled blades extend. The pair of blades dig into the ridge of the earth on adjacent pairs of rows of peanut vines. The diggers dig underneath the vines to extract the vines and peanut crop from the earth. The peanut harvester also includes a shaker assembly. The shaker assembly has large discs which are rotated and bumped and agitated as the peanut vines move across the shaker after being dug from the ground. The shaker shakes dirt from the roots of the peanut vines. Finally, the peanut harvester has an inverter section for turning the peanut vines over, in order to expose the peanuts to air for drying. The inverter thereafter deposits the inverted vines on the ground.
Typical peanut digger/shaker/inverter assemblies are designed to harvest peanut vines from adjacent pairs of rows of vines. The harvester connects to a tool bar which attaches to a tractor that pulls the digger/shaker/inverter through the field of peanuts.
In order to harvest additional rows during a single pass of the tractor through the field, some manufacturers provide what is known as multi-row peanut harvesters. Multi-row peanut harvesters place two or three digger/shaker/inverter assemblies to a single tool bar. Thus, a three unit DSI harvest six adjacent rows of peanuts at a single pass. Each DSI is driven by a chain drive having sprocket wheels and chains. The sprockets are driven by the drive shaft from the tractor.
While the multi-unit peanut harvesters reduce the time required for harvesting peanuts, these devices have not been entirely satisfactory. The multi-unit DSIs attach to the single elongate tool bar attached to the tractor. Each unit accordingly is at the same vertical height as the adjacent units. However, many peanut fields are not level and there may be a significant difference in elevation even between closely spaced rows of peanuts. In such circumstance, multi-unit DSIs are not feasible on fields that have terraces or uneven surfaces. Plows may be above ground on one side of the set of rows being harvested or in the center, while going excessively deep in some other area. Plows which are too shallow do not harvest the root crop. Plows which are too deep likewise are inefficient and remove excessive soil around the crop which prevents the crop from drying when inverted. Accordingly, multi-unit DSIs work particularly well if soil surface is level. Much of the peanut growing region however does not have level soil surface because of hillsides and terraces which define a undulating surface for the ground.
In these soil regions, the inefficiency of the harvest while using multiple-unit DSIs are so significant, that single unit DSIs are required for harvest. Accordingly, farmers are able to harvest only two rows at a time with a single unit DSI, and three passes through the field along the rows are required to harvest six rows. A multi-unit DSI capable of harvesting non-level adjacent rows efficiently simultaneously would immediately reduce the cost and time required to harvest root-crops such as peanuts.
Accordingly, there is a need in the art for an improved multi-row digger/shaker/inverter apparatus for use in harvesting root-crops. It is to such that the present invention is directed.